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Rivet analyses reference

DM1_1980_I140174

Cross section for $e^+e^-\to\pi^+\pi^-\pi^0$ at energies between 0.75 and 1.1 GeV.
Experiment: DM1 (ACO)
Inspire ID: 140174
Status: VALIDATED
Authors:
  • Peter Richardson
References:
  • Nucl.Phys. B172 (1980) 13-24, 1980
Beams: e+ e-
Beam energies: (0.4, 0.4); (0.4, 0.4); (0.4, 0.4); (0.4, 0.4); (0.4, 0.4); (0.4, 0.4); (0.4, 0.4); (0.4, 0.4); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5) GeV
Run details:
  • e+e- to hadrons

Measurement of the cross section for $e^+e^-\to\pi^+\pi^-\pi^0$ at energies between 0.75 and 1.1 GeV. Beam energy must be specified as analysis option "ENERGY" when rivet-merging samples.

Source code: DM1_1980_I140174.cc
 1// -*- C++ -*-
 2#include "Rivet/Analysis.hh"
 3#include "Rivet/Projections/FinalState.hh"
 4#include "Rivet/Projections/UnstableParticles.hh"
 5
 6namespace Rivet {
 7
 8
 9  /// @brief e+ e- > pi+ pi- pi0
10  class DM1_1980_I140174 : public Analysis {
11  public:
12
13    /// Constructor
14    RIVET_DEFAULT_ANALYSIS_CTOR(DM1_1980_I140174);
15
16
17    /// @name Analysis methods
18    /// @{
19
20    /// Book histograms and initialise projections before the run
21    void init() {
22      // Initialise and register projections
23      declare(FinalState(), "FS");
24      declare(UnstableParticles(), "UFS");
25      book(_n3pi, 1, 1, 1);
26      for (const string& en : _n3pi.binning().edges<0>()) {
27        double end = std::stod(en)*MeV;
28        if(isCompatibleWithSqrtS(end)) {
29          _ecms = en;
30          break;
31        }
32      }
33      if(_ecms.empty()) MSG_ERROR("Beam energy incompatible with analysis.");
34    }
35
36
37    /// Perform the per-event analysis
38    void analyze(const Event& event) {
39      const FinalState& fs = apply<FinalState>(event, "FS");
40
41      map<long,int> nCount;
42      int ntotal(0);
43      for (const Particle& p : fs.particles()) {
44	nCount[p.pid()] += 1;
45	++ntotal;
46      }
47      if(ntotal==3 && nCount[211] == 1 && nCount[-211] == 1 && nCount[111] == 1)
48	_n3pi->fill(_ecms);
49    }
50
51
52    /// Normalise histograms etc., after the run
53    void finalize() {
54      scale(_n3pi, crossSection()/ sumOfWeights() /nanobarn);
55    }
56
57    /// @}
58
59
60    /// @name Histograms
61    /// @{
62    BinnedHistoPtr<string> _n3pi;
63    string _ecms;
64    /// @}
65
66
67  };
68
69
70  RIVET_DECLARE_PLUGIN(DM1_1980_I140174);
71
72
73}